1. Field of the Invention
The invention relates to foam molding. More specifically, the invention relates to the transport of foam from a foam nozzle to a mold cavity.
2. Description of the Related Art
Efficiencies are required in the manufacture of motor vehicles. One area where efficiencies are required is in the area of foam molding. With the intricate designs of many of the molded parts, a different size nozzle would be required for each part. Further, depending on the size or profile of the part, the relative height of the mold cavity may vary. This would require the height of the platform on which the mold cavity sits to vary. Adjusting the foam assembly, i.e., the foam nozzle with respect to the conveyer system upon which a mold assembly might rest, must be adjusted for each differently shaped piece which is to be molded. Further, it may be impossible to move a long foam nozzle out of the way of the mold piece as the mold piece moves to and from the foaming station. In other words, the relative distance the foam nozzle would have to move to clear the mold piece to allow the mold piece to move away from the foaming station would be too great.
Two alternatives may exist for handling different sized mold parts. The first is to have a different mold assembly and line, or sub-line, for each different part being manufactured. This is costly for manufacturers as the size of plants and the amount of equipment would increase to a point of making the manufacturer uncompetitive. A second alternative is to stop the production line and replace the nozzle head or adjust the height of the mold platform upon which the mold sits. This is not a realistic option because the down time of the production line would increase the cycle time and, hence, the cost of the parts being manufactured.
The two options may not even be available to a manufacturer if the design of the mold is such that it requires the mold platform to be at a specific height. In particular, the profile of the mold cavity may be such that the mold cavity will prevent a long nozzle head from being employed because the long nozzle head would obstruct the path of the mold cavity as it passed by or closed under the long nozzle head.
U.S. Pat. No. 4,993,596, issued to Brown on Feb. 19, 1991, discloses a gun styled chemical injector. The gun includes an elongated discharge valve assembly. This elongated discharge valve assembly is removable for maintenance or replacement. While the elongated discharge valve assembly is removable, it is designed to be secured between an inlet port and an outlet port of the gun. Therefore, the overall size of the gun does not change. Because the size or length between the inlet and outlet ports is not important in a portable device, this reference does not address systems of such volume that require large delivery systems where the length of the foam nozzle is important to an automated mold assembly line. More specifically, this patent does not address issues relating to the delivery of foam to mold cavities that are of such volume, that something as position and orientation manipulatable as a hand held dispensing device such as a gun is not appropriate.